Picture: Supplied
Picture: Supplied

The world’s largest 3D printer is right here in SA, and it is already at work turning powder into large metal components for the aerospace sector.

The printer — or more accurately, a metal additive manufacturing system — is housed at the Council for Scientific & Industrial Research (CSIR) in Pretoria. It is part of Aeroswift, a project funded by the science & innovation department to industrialise and commercialise the printer’s technology. It cost R100m to build.

The CSIR and Aerosud Innovation Centre — a subsidiary of aircraft manufacturer Aerospace Development Corp — saw the potential of this technology as far back as 2011, and have since designed, built and manufactured an advanced 3D printer — all in SA.

The CSIR hopes to secure contracts with international suppliers, and thanks to an existing relationship with Airbus, is in negotiations to print parts for the European aircraft maker.

Additive manufacturing is a relatively new manufacturing technology. It is considered one of the key technologies that will support the production of high-value parts for industries such as aerospace. Additive manufacturing fuses materials together, layer by layer, into 3D functioning parts that are lighter and stronger than standard parts.

The 3D printer uses lasers to melt titanium powder to produce the metal parts.

Some of Aeroswift’s research breakthroughs include 3D-printed parts such as a pilot’s throttle lever and a condition lever grip for the locally developed Ahrlac (an acronym for advanced high-performance reconnaissance light aircraft); a fuel tank pylon bracket for a commercial aircraft; a missile boat tail; and a drone frame.

Lerato Tshabalala, research group leader at the CSIR, says it was an ambitious approach to introduce the technology in SA. Its aim was to build a high-speed, high-powered system that could generate large parts.

"The system has the ability to produce geometrically complex parts according to a customer’s specification, minimising material wastage while processing difficult-to-machine materials," she says. "The system can also be used to produce parts for the power generation, automotive tooling, defence and manufacturing sectors."

Picture: Supplied
Picture: Supplied

The 3D printer can print components up to 2m long, 600mm wide and 600mm high. The CSIR says the Aeroswift team developed new technologies to upscale the additive process to go faster and larger than other systems, and achieved production speeds of up to 10 times faster than current commercial laser melting machines. This is due to the 3D printer using a 5kW laser – compared to commercial machines powered with 800W. It is able to print four designs at the same time.

The material used — titanium — was a natural choice, says Tshabalala. SA has some of the world’s largest reserves of the metal and it is building a strategy of beneficiation of the metal.

Jacobus Prinsloo, operations manager at Aeroswift, says with the focus being aerospace, titanium was the natural choice to go for because the alloy used is aerospace certified.

Aeroswift’s main goal is to transform the country from an exporter of raw material to an exporter of semi-finished or finished goods, which can be sold at a premium compared with the material in its raw state.

Operating the Aeroswift printer is a 15-person team effort. "There are only two people who are able to do all the tasks, and below them are others focused on specific areas," says Prinsloo. These include handling the powder, making the lines of scraper, and making sure that the powder is processed properly, in addition to starting up the printer, monitoring the process and making sure the machine runs as it should.

"To start up the machine it’s a four-to five-person job to get all the components working together, which takes a couple of hours to prepare," says Prinsloo. "The machine will be running in principle for six days, and you don’t want to find out afterwards that you installed the wrong plates."

The Aeroswift printer is different from commercially available machines, he says. "We have a much higher laser power and we can build much larger parts; and we’re still the largest machine in the world."

Prinsloo says a lot of its functionality has been patented. There are some differences in "how we run our systems that set it apart from the rest of the world".

Tshabalala points out that the printer is not a commercial system: "It is a research & development platform that will stimulate businesses to invest in the technology. We can manufacture similar or customised parts in 3D printing."

However, it’s not as simple as a client approaching the CSIR to print parts.

"There is a full value chain around it, including a design aspect," says Tshabalala.

"If you understand the design aspect and you can actually design for additive manufacturing, that’s part of the learning aspect that we encourage and introduce people to.

"From there, we define the criteria for building those parts and see if it is financially viable to print. 3D printing is not meant to replace conventional manufacturing, but rather enhance areas that cannot be achieved through conventional manufacturing like complex designs," she says.